Question about the vvti and engine limiter in Spec V

[NX 2000]

>From: "SpecV Rulez" <specv@hotmail.com>

>Well, this specv reaches its power peak at 6000 RPM. It cuts at 6500 RPM.
>Would it be better to take the engine limiter of to make it go faster or
>not, or is it possible to take it off?

Since no one has taken the Qr25DE motor on a dyno to show what the power is
like above 6250 rpms, there is no deffinate answer to this question. Only
way to rev the QR25DE past 6250 rpms is to down shift the car, and that is
not advised.  Or else wait for the JWT ECU.

>Question number two is vvti kicks in at 5000 RPM angine cuts at 6500RPM so
>i
>shift at 6200 RPM, which gives me about 1200 RPM of power band. Now what i
>wanna now is would using a vvti controller to drop it to 4000 RPM work?

VVTi is the Toyota variable valve thing.
The QR25DE has CVTC, continuous variable timing control.
The ecu continuously controls the intake cam timing to optimize performance.
  Unless you dyno it, there is no sure way tell if there may be any gains
from controling the timing yourselve.
VVTI, and Vtec controllers will not work because these motors do not have
secondary lobes the the other 2.

Is
>the thing which kikcs in at 5000 RPM is the variable short air intake
>instead of the vvti which runs contuniosly they say? If it is the new and
>shorter and cooler air intake, is there a way to drop the rpm of that
>things
>start?

Check the archieves first and check www.B15sentra.net.
The thing you hear at 5000 rpms is the short runner intake.  It is supposed
to help with top end and better throttle response.
But teh air is not cooler.  You'd have to make your own cold air intake for
that.

>They say this car gets its 10 more horspower than the SE-R is because of
>its
>modified air intake and specially tuned exhaust. So if i get a different
>exhaust and a new cold air intake would I only increase like 2 horspower
>because i am taking something out which already increses the horspower like
>10 and put another thing in which gives 12 horsepower.

No one has these mods yet so no one knows for sure.  Check the archives on
b15 because VBSPECV dyno's his spec V, ran a baseline and one with an open
intake and another without the rear section of the exhaust.
Another thread has a picture of a dyno graph of the Spec V with an AEM
prototype cold air intake and stock everything else and that gained 7 hp's
and 11 ft/lb max and lots of area under the curve from 2500 to 45000 rpm's.

The car is too new and not enough testing has been done.  You can be
innovative and get a muffler shop to make a custom 2.5 inch exhaust.  That
should free up some ponies because the stock exhaust has sections that
funnel down to less than 1.75 inches and there are 2 resonators before the
muffler.  And replaceing just the rear section has freed up a few ponies.
I've done my own DIY funnel intake and I highly recomend that too.

Edwen Ma
02 Spec V
92 NX2000 hybrid =P